The arrests come after Ayatollah Montazeri issued a new statement in which he urges leading Shi'ite clerics and "sources of emulation" to break their silence over the crackdown following Iran's disputed June 12 presidential election.

He said the Iranian government of President Mahmud Ahmadinejad is "exploiting the silence of the clergy."

Ayatollah Montazeri referred to the rule of Iranian Supreme Leader Ayatollah Ali Khamenei as "military rule" and said he regrets his role in including the Velayat Faghih -- or rule of the supreme jurist -- in the Iranian Constitution.

Ahmad Montazeri told Radio Farda that he doesn't believe the arrests of his children were connected to the critical statement by his father.